I just turned-off dynamic sampling and it behaved as expected. Means, 1
version_count in case of similar and exact cursor_sharing setting.

But, even in case of dynamic sampling, table data is not skewed and
histogram is of no use in this case. Thi can be checked even from
plan_hash_value of child cursors. Execution plan is same. Then why Oracle is
creating multiple child.

Disabling the bind value peeking, resulting in three parent cursors. I
didn't know any reason for that.